When considering the CFC in different frequency bands, besides gamma/theta CFC, studies have found that CFC coupling between alpha, beta, and gamma may play an important role in coordination in perception, consciousness, and working memory (Palva and Palva, 2007). Furthermore, beta–delta CFC has been associated with neuropsychiatric symptoms, which is also prevalent in patients with AD (Miskovic et al., 2010). Therefore, couplings between other frequencies besides gamma/theta CFC may also be disrupted in both AD and MCI.
